Method for preparing active carrier particles of equal size for a polymerization catalyst

Abstract

PCT No. PCT/FI92/00170 Sec. 371 Date Nov. 30, 1993 Sec. 102(e) Date Nov. 30, 1993 PCT Filed May 29, 1992 PCT Pub. No. WO92/21705 PCT Pub. Date Dec. 10, 1992The active carrier particles of even size of the polymerization catalyst are prepared so that a melt of a complex composition is provided having the formula (I)MgCl2 nROH mED(I)in which ROH depicts an aliphatic alcohol, R is a C1-C6 alkyl, ED depicts an electron donor, n is 1 to 6 and m is 0 to 1; the melt provided is fed to a nozzle (4); the melt is sprayed from the nozzle (4) to the spraying area (5), in which it is divided into fine melt droplets and possibly partly solidifies; the possibly partly solidified melt particles are transferred to a cooled crystallization area (6), where they crystallize to solid carrier particles; and the solid carrier particles are recovered. The melt mentioned is sprayed through a nozzle (4), which is rotated or which has attached to it a member that rotates and throws melt outwards from the rotating center to the spraying area (5).

What is claimed is: 
     
       1. A method for the preparation of solid non-porous carrier particles for a polymerization catalyst, said particles being loose and of equal size, comprising the steps of feeding a melt of a complex compound having formula (I)   MgCl.sub.2 nROH mED                                        (I)     wherein ROH is an aliphatic alcohol, R is an alkyl group having 1 to 6 carbon atoms, ED is an electron donor, n is 1 to 6, and m is 0 to 1, to a rotating nozzle;     spraying the melt from the nozzle to a spraying area inside a vessel, while conducting inert gas at a temperature of 20° to 40° C. into an area of the vessel near the nozzle in the same direction as the rotation of the nozzle, thereby throwing the melt outward from the rotating center of the nozzle to the spraying area and dividing the melt into fine melt droplets; and   transferring the melt droplets to a crystallization area into which inert gas is introduced at a temperature of -50° to 20° C., and crystallizing the melt droplets into nonagglomerated solid non-porous carrier particles which are loose and of equal size.   
     
     
       2. A method according to claim 1 for the preparation of solid non-porous carrier particles for an olefin polymerization catalyst, said particles being loose and of equal size, comprising the steps of providing a melt of a complex compound having formula (I)   MgCl.sub.2 nROH mED                                        (I)     in which ROH is an aliphatic alcohol, R is an alkyl having 1 to 6 carbon atoms, ED is an electron donor, n is 1 to 6 and m is 0 to 1;     feeding the melt to a hollow disc nozzle having a closed structure that is rotated at a speed of about 10,000 to 30,000 rpm, at a temperature of about 100 to 140° C. and at a feeding rate of about 10 to 50 kg/h;   spraying the melt from the nozzle to a spraying area of a vessel that has inert gas at a temperature of 20° to 40° C. conducted into the spraying area near the nozzle in the same direction as the rotation of the nozzle, wherein the melt is thrown outward from the rotating center of the nozzle to the spraying area and is divided into fine melt droplets;   transferring said fine melt droplets to a crystallization area into which inert gas is introduced at a temperature of -50° to 20° C., where said melt droplets crystallize into nonagglomerated solid non-porous carrier particles which are loose and of equal size; and   recovering said nonagglomerated solid non-porous carrier particles.   
     
     
       3. A method of making a procatalyst for the polymnerization of olefins, comprising contacting the recovered solid carrier particles obtained from the process of claim 2 with a transition metal compound and optionally with an internal electron donor, and recovering said procatalyst. 
     
     
       4. The method according to claim 3, wherein the transition metal compound is titanium tetrachloride. 
     
     
       5. The method according to claim 1 wherein the speed of rotation of the nozzle is about 18,000 to 25,000 rpm. 
     
     
       6. The method according to claim 1 wherein the nozzle is a hollow disc nozzle which rotates around its axis and comprising surface holes in its outer periphery, wherein the melt is forced out through said surface holes by the aid of centrifugal force. 
     
     
       7. The method according to claim 6, wherein the diameter of the hollow disc nozzle is about 100 to 150 mm. 
     
     
       8. The method according to claim 6, wherein the hollow disc nozzle has four outer periphery surface holes, each having a diameter of about 4 mm. 
     
     
       9. The method according to claim 6, wherein the hollow disc nozzle has a hollow space between an inlet opening in contact with a feeder pipe for the melt and the outer periphery surface holes. 
     
     
       10. The method according to claim 1, wherein the inert gas, which is directed to the spraying area close to the nozzle, has a temperature of about 20 to 40° C. and a flow rate of about 500 kg/h. 
     
     
       11. The method according to claim 10, wherein the inert gas is directed by the aid of a dividing plate so that the inert gas circulates in the same direction as the rotating nozzle. 
     
     
       12. The method according to claim 1, wherein said vessel is a vertical chamber having the rotating nozzle in an upper end, the spraying area in an upper portion, the crystallization area in a lower portion, and a recovery opening for recovering the solid carrier particles in a lower end. 
     
     
       13. The method according to claim 12, wherein inert gas is conducted through a pipe to the crystallization area or between the spraying area and the crystallization area. 
     
     
       14. The method according to claim 13, wherein the temperature of inert gas fed to the crystallization area, or between the spraying area and the crystallization area, is -50 to +20° C. and the flow rate is about 300 kg/h. 
     
     
       15. The method according to claim 1, wherein ROH is ethanol, and n is 3 to 4. 
     
     
       16. The method according to claim 1, wherein ED is dialkyl phthalate or dialkyl maleate. 
     
     
       17. The method according to claim 16, wherein ED is diisobutyl phthalate or diethyl maleate. 
     
     
       18. The method according to claim 1, wherein m is about 0.05. 
     
     
       19. The method according to claim 1, wherein the nozzle rotates at a speed of about 10,000 to 30,000 rpm.